2022
Your app deservers its own CLI: Try sidekick
October 28, 2022
@ Droidcon London 22, London
With Flutter we don’t have a modular build system like Gradle. But where should you put your code to automate your CI/CD process?
A simple bash script in your /tool directory is a good start, but to be honest: None of us is “good at bash” and nobody really wants to learn it. It doesn’t scale, doesn’t support dependencies and is not testable.
Getting started with Functional Programming
October 28, 2022
@ Droidcon London 22, London
Object Oriented Programming is on a decline in popularity since 2010, while Functional Programming experience a second hype. Most new languages today are a mix of both, functional and object-oriented.
What’s new in Flutter 3.0
May 23, 2022
@ flutter.school, Düsseldorf
So if you’re just getting started or are a senior in our school, this event is for you! We’ll begin with a short intro to Flutter and its ecosystem followed by a chat about the fresh Flutter updates from this year’s Google I/O by our very own Google Developer Expert Pascal Welsch.
2021
Testing and Debugging Flutter applications (Workshop)
July 27, 2021@ geekly Flutter Summit 21 online
Join your first Coding Dojo and let us together solve a problem in a test-driven way. With TDD in mind we’ll split the task in tiny problems which can be solved by writing tests first!
The goal is not to solve the task in all aspects, but to practice our skills while having fun. Along the way we’ll cover
Covid break
January 1, 2021Due to COVID-19 I stopped all plans for in-person Meetups/Conferences. Meanwhile, follow me on Twitter to get updated about live streams, library releases and fun.
Stay healthy at home!
2020
Immutability in Dart and Flutter
June 26, 2020
First Youtube experiement. Quick introduction into immutability in Dart/Flutter
Making Dart more like Kotlin
March 11, 2020
@ mobile.cologne
Kotlin is one of the best-designed languages, which makes it easy to express developer thoughts in code. But Dart gets better, quickly!I’d like to present what the Dart Team is working on to make the language as much fun as Kotlin. The Flutter community isn’t standing still and improves the ecosystem themselves. Let me introduce kt.dart, dartx and freeze.
Pascal Welsch, Flutter GDE, will demonstrate how kt.dart can prevent bugs by using immutable data structures, which respect equality and reduce code complexity with extensions.
Practical State Management in Flutter
March 5, 2020
@ GDG Freiburg
We are happy to announce that we will be hosting our very first Google Developer Expert!
Pascal is a GDE for Flutter who will visit us from Cologne and give us up-to-date insights into Flutter!
Newcomers to Flutter invest days in deciding on a good state management solution. Time in which others ship first features. Let’s take a shortcut and look at a few solutions out there, their weaknesses and strengths. Let me tell you why BLoC is probably not right for you and why MVP doesn’t fit into the flutterverese.
After this talk you will have a good overview of the different solutions and an expert tip on how to get started.
Making Dart more like Kotlin
February 19, 2020
@ Flutter Munich
Do you miss Kotlin when building Flutter Applications? I do. Kotlin is one of the best-designed languages, which makes it easy to express developer thoughts in code. But Dart gets better, quickly!I’d like to present what the Dart Team is working on to make the language as much fun as Kotlin. The Flutter community isn’t standing still and improves the ecosystem themselves. Let me introduce kt.dart, dartx and freezed.
Aus Zwei wird Eins: App-Relaunch bei Durst mit Flutter
February 11, 2020
@ MORE MOBILE MEETUP, Cologne
Deine App. Tatsächlich besteht sie aus drei Apps. Eine pro Platform: Android, iOS und Web; gebaut von drei verschiedenen Teams. Wie stellst du sicher, dass alle Kunden gleiche Qualität erleben?
Möglich ist das mit Flutter, einem Multi-Platform Framework von Google, mit dem alle Entwickler an der gleichen App arbeiten. Ein Team, drei Apps. So landet jeder investierte Euro in die App Entwicklung bei allen Kunden.
Masterplan: Migration to Flutter
February 6, 2020
@ flutter.school, Cologne
Pascal Welsch from a Cologne based Flutter Agency Handsome will showcase a successful migration from native to Flutter and a Checklist you can follow to ease your own migration.
2019
Understanding Declarative UI – The hype of React, SwiftUI, Flutter and Jetpack Compose
December 14, 2019
@ DevFest Nuremberg 2019
SwiftUI and Jetpack Compose are the latest additions to native iOS and Android development. Both are UI frameworks which feature a declarative style, similar to React and Flutter.
The transition from imperative to declarative UI is huge. It requires a mindset change! Instead of mutating individual widgets you have to define states and render them. Which first might seem like a weakness and way too much boilerplate code is the biggest strength of that design.
The old, imperative way of writing user interfaces is still used in millions of apps. Your codebase is most likely one of them! This talk will show you a migration path to prepare your apps for declarative UIs until SwiftUI and Jetpack Compose become stable.
Although all those frameworks let you define UIs in a declarative way, there are huge differences in how they work internally. It’s not fair to compare them, since they are designed for different platforms. But this doesn’t mean interesting facts and differences in their implementation can’t be pointed out.
kt.dart – Porting Kotlin’s best features to Dart
November 11, 2019
@ Flutter London
Kotlin is one of the best designed languages, which makes it easy to express developer thoughts in code. Sadly, we can’t use Kotlin to write Flutter apps. But the Dart team at Google is working to adopt kotlins best language features: Extensions Methods, Non-Nullable Types and Data Classes.
kt.dart ports kotlins well designed collections, tuples and hundreds of extension functions from the kotlin-stdlib to Dart. You can use it today in your Flutter project and while dart-lang evolves, kt.dart becomes even better.
Pascal Welsch – Flutter GDE from Cologne, Germany – will demonstrate how kt.dart can prevent bugs by using immutable data structures, which respect equality and reduce code complexity with extensions.
Flutter Teams build better products
November 9, 2019
@ DevFest Karlsruhe 2019
Flutter, now one year stable, is becoming the de facto standard for multi-platform apps. But what does this mean for companies and agencies? A huge opportunity to build better products!
Combining teams which usually never touch each others code creates friction. But given all the benefits of a large diverse team, working on the same codebase is definitely worth it.
Learn from teams which actually moved from native to Flutter and their best practices.
Why is flutter good for companies
- Maintenance of multiple platforms from a single person
- Declarative UIs are easy for web developers. Easy to find developers
- Easy to learn
- Prototypes are the final product
- Close collaboration with your designer
- Multi platform – for free*
- diversity by different backgrounds
Flutter fly – Introduction to kt.dart
November 6, 2019
@ GDG Nuremberg
We are very happy to host Pascal Welsch again, Google Developer Expert for Flutter. Pascal is one of the pioneers when it comes to adopting this technology. He’s been using flutter since its first days.
Pascal will talk about his library kt.dart, which is a port of Kotlin’s Standard Library and adds some sugar to the everyday development with Dart.
Flutter Study Jam + Talk “Flutter teams build and better products”
November 2, 2019
@ DevFest Hamburg 2019
11:00:
Flutter Study Jam.
14:00:
Flutter, now one year stable, is becoming the de facto standard for multi-platform apps. But what does this mean for companies and agencies? A huge opportunity to build better products!
Combining teams which usually never touch each others code creates friction. But given all the benefits of a large diverse team, working on the same codebase is definitely worth it.
Learn from teams which actually moved from native to Flutter and their best practices.
Flutter teams build and better products
October 24, 2019
@ codemotion Milan 2019
Flutter, now one year stable, is becoming the de facto standard for multi-platform apps. But what does this mean for companies and agencies? A huge opportunity to build better products! Combining teams which usually never touch each others code creates friction. But given all the benefits of a large diverse team, working on the same codebase is definitely worth it. Learn from teams which actually moved from native to Flutter and their best practices.
What’s new in Flutter
October 19, 2019
@ DevFest Würzburg 2019
Using Flutter? Even if you do, it is hard to keep track of all the new features which get added to the Flutter SDK every week. Pascal Welsch – Flutter GDE from Cologne – will talk about latest significant additions and a give a lookout what’s currently in the baking, which will be significant in the future.
Understanding Declarative UI – The hype of React, SwiftUI, Flutter and Jetpack Compose
August 6, 2019
@ Talk im Park #4
SwiftUI and Jetpack Compose are the latest additions to native iOS and Android development. Both are UI frameworks which feature a declarative style, similar to React and Flutter.
The transition from imperative to declarative UI is huge. It requires a mindset change! Instead of mutating individual widgets you have to define states and render them. Which first might seem like a weakness and way too much boilerplate code is the biggest strength of that design.
The old, imperative way of writing user interfaces is still used in millions of apps. Your codebase is most likely one of them! This talk will show you a migration path to prepare your apps for declarative UIs until SwiftUI and Jetpack Compose become stable.
Although all those frameworks let you define UIs in a declarative way, there are huge differences in how they work internally. It’s not fair to compare them, since they are designed for different platforms. But this doesn’t mean interesting facts and differences in their implementation can’t be pointed out.
Step up your tooling
July 3, 2019
@ Droidcon Berlin 2019
GitHub, Slack, Jira, SourceTree, Jenkins, Sketch… RING!, RING! 2015 Called! It wants its software stack back.
Remember when you switched from Eclipse to Android Studio? It wasn’t easy but totally worth it. To be productive you can’t test every new tool out there. At some point, you have to stick to what you got and over time you forget about the workarounds you’re doing every day.
I did test tons of programs and present you 10 new tools for developers you don’t want to miss for a productivity boost. It’s time to bump up your software stack!
Dart 2.3
May 22, 2019
@ flutter.school, Düsseldorf
Small introduction into the latest changes in Dart 2.3. This releases addresses Flutter developers daily challenges with the dart language. The new language features makes it easy to build user interfaces without the need for a markup language. Welcome spread operator, collection if and collection for.
Flutter Study Jam / Hot Reload Hackathon for Beginners
March 12, 2019
@ flutter.school, Cologne
This event is for you if you are new to Flutter or just starting out (for sure you can also join when you are already an expert) and want to build your first app for Android and iOS.
We will start around 4pm at the grandcentrix headquarter in Cologne where Pascal and I will give a short intro to Flutter. You’ll be instructed to build a Flutter app beyond “Hello World”.
We’ll clone a popular app together with Firebase, and fancy animations. From zero to hero in only a few hours!
Continuous Integration with Flutter
February 26, 2019
@ flutter.school, Düsseldorf
Introduction into CI with Flutter. A presentation about the tools used to make CI with Flutter a success. Lint, code-coverage until automatic publishing to the stores.
CI with Flutter, done right
February 12, 2019
@ mobile.cologne, Cologne
Talk about building CI for Flutter apps, independent of the underlying CI environment. I demonstrate Jenkins and Gitlab as examples.
Build, test and static analysis like lint and code coverage included.
2018
Heavy lift work in Flutter – get started with Isolates
October 12, 2018@ DevFest Ukraine 2018, Lviv
Moving work off the main thread prevents frame drops and makes users happy. Starting with Android P, apps will crash if they are not responding forcing developers to address this problem even more. Working with threads and async computations is every mobile developers daily challenge.
Flutter uses Dart, which is single threaded and has no APIs to start a new threads like in Java or Swift. How does this fit in a world of phones with at least 4 CPUs?
This talk will explain the Flutter threading model, how Futures keep the app responsive on a single thread and how you can use all CPU cores for compute heavy task via Isolates.
Flutter Introduction & Codelab
June 13, 2018
@ GDG Nuremberg Android
Flutter Google Developer Expert (GDE) Pascal Welsch will pay us a visit and introduce us in his talk to Flutter.
What’s new about Flutter? Why is it not just another cross-platform development tool? When does it make sense to use it? There are definitely a lot of questions which Pascal will be able to answer.
Afterwards, we’ll do a Codelab on Flutter.
10 years Android – what’s next? Fuchsia and Flutter
March 1, 2018@ mobile.cologne, Cologne
The Android UI evolved a lot in the last decade. With Holo, Android became kind of nice looking and with Material Design, Android became beautiful. What hasn’t changed is the UI Framework where layouts are inflated, layouted and measured on the main thread. Decisions made in 2005 which can’t be changed now. This makes it harder than it should to run you app constantly on 60fps.
Flutter, a mobile app SDK from Google is designed to render your app constantly at 60fps. It already comes with a rich catalog of pixel perfect Material Design which look and feel like widgets from the Android design support library. Flutter apps are written in Dart and cross compile to Android and iOS to native code (not JavaScript!!!). Java glue code is only required when you’re talking to system services like GPS or notifications.
Flutter could be Googles transition plan for Fuchsia, Googles next operating system for mobile devices. Instead of supporting Android Apps on Fuchsia, apps for Fuchsia can be compiled to iOS and Android apps. Fuchsia supports Dart as first class language and the system UI is written with flutter.
It’s time to look what’s next!
even earlier
ThirtyInch – Introduction to the MVP library
December 11, 2017@ GDG Düsseldorf
Testing on Android is hard. Activities aren’t really testable, and if not as unit test on the JVM. But with a clever abstraction, most of our UI logic actually can be tested. This talk introduces ThirtyInch, a MVP library for Android.
It compares ThirtyInch to other MVP implementations existing in the wild which often try to be stateless. ThirtyInch tries to be stateful and outlives the Activity lifecycle during configuration changes.
Please keep in mind, this was before Google Announced Architecture Components and ViewModels. ThirtyInch Presenters where back then, the ViewModels you know today from Android Jetpack.
Kotlin in production – One year later
July 13, 2017
@ GDG Düsseldorf
Thanks to the community, Kotlin became the new language for Android Apps. Pascal Welsch is already using Kotlin for over an year in production and will talk about his learnings covering features and tools you should use and other which are too risky for a long term project.Thinking about adopting Kotlin in your project? Pascal shows the process of adopting Kotlin in all Android Apps at grandcentrix.
Introduction to Bluetooth 5
February 15, 2017
Bluetooth 5 -> The Bluetooth SIG released the specification of Bluetooth 5 in December ’16. This release will lay the foundation of future IoT devices: longer range (4x), faster speed (2x), bigger messages (8x)
Pascal Welsch from Grandcentrix will cover the new possibilities, backwards compatibility and how this new protocol will affect future products. Grandcentrix is Germany’s largest systems integrator specialized in the end-to-end creation of digital products and services for the Internet of Things, Smart Home and Mobile Commerce, and we are excited to once again have Pascal come and present.
Get Reactive – Introduction to RxJava
November 12, 2015@ Devoxx Belgium November 2015, Antwerp
The RxJava hype is still in full swing and almost everything gets Rxified. At least since the stable RxAndroid 1.0 release, it’s time to take RxAndroid seriously!
In this session, you will learn what RxJava is about, how to use it on Android and how RxAndroid can be used to build maintainable Android Apps from networking with Retrofit2 to UI with the new RxBinding and RxLifecycle libraries powered by MVP.
If you haven’t had the time to Get Reactive, we’ll provide a quick introduction why you should use RxAndroid in your current and next projects.
Material Design Introduction
February 9, 2015@ mobile.cologne
(German) Introduction into Material Design, Androids new design language in Android Lollipop.
Upcoming
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No future talks confirmed, yet.